DTC Troubleshooting: 81
DTC 81:
 Engine Control System (Including ECM/PCM) Malfunction
Are any DTCs indicated?
YES -
Troubleshoot the indicated PGM-FI system DTC(s).■
NO -
Go to Step 2 .
  1. Test-drive the vehicle with the adaptive cruise control (ACC) activated.
Is DTC 81 indicated?
YES -
Check for loose or poor connections. If the connections are OK, update the ACC unit, then recheck. If the ACC unit was already updated, replace the ACC unit. ■
NO -
Intermittent failure. The system is OK at this time. Check for loose or poor connections.■